1. Field of the Invention
This invention relates to a coil failure detection system for a general-purpose internal combustion engine.
2. Description of the Related Art
Japanese Laid-Open Patent Application No. 2005-76522 is one of a number of recently published references describing use of an actuator for regulating throttle opening in the type of general-purpose engine or industrial engine used as a prime mover in generators, agricultural machines and various other applications. The technique described in the reference calls for the provision of coils for generating outputs in response to rotation of the engine output shaft. One of the coils produces an output indicating engine speed and the throttle opening is regulated by controlling the operation of the actuator based on the output of this coil as one factor.
In the conventional arrangement, however, the engine is liable to experience a problem such as overrunning if the coil producing the output indicating engine speed breaks and fails, because in such case the engine speed cannot be detected so that throttle opening regulation becomes impossible. Detection of coil failure is therefore desirable for avoiding the occurrence of such problems.